Since returning to F1 as reigning GP2 champion this year, the French driver has been often praised for his pace but labelled a "first-lap nutcase" by Mark Webber following numerous early-race accidents.

He served an ultra-rare one-race ban at Monza but last weekend caused yet another incident at the start of the Japanese grand prix.

F1 chief executive Ecclestone thinks he could have a vision problem.

"Lotus should take him away and get all the tests done," he is quoted by The Times newspaper.

"It seems to me that he is a very fast driver but seems to have trouble in seeing what is around him. A lot of what has happened to him this season has involved not being able to react to things happening in his peripheral vision.

"That could be the problem. If it was up to me, I would have him stand down for a grand prix, send him for every test and be sure that his eyesight was ok.